<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style type="text/css">
			div{
				width: 300px;
				height: 300px;
				background: yellow;
			}
		</style>
	</head>
	<body>
		<div>
			黑马程序员
		</div>
	</body>
</html>
